Table II.

DRB1 and DRB5 frequencies in African American MS cases and controls^a

	Cases		Controls
	Frequency	Count	Frequency	Count	Odds Ratioc	95% CI	p Value
DRB1-DRB5 alleles
DRB1*15b	0.209	322	0.147	237	1.53	1.27–1.85	<0.0001
DRB1*1501	0.064	98	0.029	47	2.35	1.63–3.43	<0.0001
DRB1*1503	0.146	224	0.118	190	1.33	1.07–1.65	0.008
DRB1*03	0.162	216	0.133	99	1.35	1.03–1.78	0.02
DRB5	0.214	330	0.163	262	1.40	1.17–1.69	0.0002
DRB1-DRB5 haplotypes
1501-0101	0.064	98	0.029	47	2.35	1.62–3.43	<0.0001
1502-0101	0.003	4	0	0
1502-0102	0.001	1	0	0
1503-0101	0.133	205	0.114	183	1.26	1.01–1.57	<0.04
1503-0104	0.001	1	0	0
1503-null	0.012	18	0.004	7	2.89	1.15–8.22	0.015
16-0101	0	0	0.001	2
16-0102	0	0	0.001	1
16-0202	0.014	21	0.017	28
16-0203	0	0	0.001	1
X-null	0.774	1,190	0.833	1,339

^aPYPOP (version 0.6.0) was used to determine haplotypes for cases and controls (including nontransmitted family-based controls; see Materials and Methods).

^bDRB1*15 consists of all DRB1*15 alleles, including DRB1*1501 and DRB1*1503.

^cOdds ratios for DRB1*15/1501/1503 were determined using DRB1*X as the reference group, where DRB1*X are non-DRB1*1501/1503 alleles (1216 case and 1371 control chromosomes). Odds ratios for DRB1*03 were restricted to individuals with complete DRB1 genotype characterization (see Materials and Methods); the reference group consisted of non-DRB1*1501/1503/03 alleles (830 cases and 515 control chromosomes). Odds ratio for DRB1*1501/1503-DRB5 haplotypes were determined using DRB1*X-DRB5*null (X-null) as the reference group, where DRB1*X are non-DRB1*1501/1503 alleles.